Background: Infection with Ureaplasma urealyticum (Uu) has been associated
with chronic lung disease in preterm infants.

Aim: To determine if infection with Uu from birth causes a specific acute
respiratory disease which may be the precursor of long term lung damage.

Methods: 60 ventilated babies <30 weeks had tracheal secretions cultured for Uu.
Clinical details in the first 10 days were reviewed retrospectively. Chest
X-rays around days 1, 5 and 10 were independently reported, for agreed features,
by 2 radiologists, blinded to the baby's Uu status. Each feature was scored 0-4
dependent on the lung quadrants involved. Comparisons were by Chi square and
Mann Whitney U test.

Results: 25 were Uu positive and in these chorioamnionitis was more common
(13/24 vs 5/30, p=0.005) and maximum white count higher (median (range) 28
(8-92) vs 19 (7-70), p=0.015). Despite being less mature (25 (24-29) vs 26
(24-29) weeks, p=0.016) the Uu+ve group were weaned earlier to the same mean
airway pressure and FiO2 as the Uu-ve group (day of lowest MAP 4 (2-10) vs 6
(1-10), p=0.039); day of lowest FiO2 2 (1-6) vs 3 (1-10), p=0.052). The Uu+ve
group then deteriorated, needing increased ventilatory support (day 10: MAP 7
(5-14) vs 5 (0-12), p=0.002; FiO2 39 (25-66) vs 25 (21-72), p=0.001). Changes of
RDS were less widespread on day 1 X-rays in the Uu +ve group (median score 1
(0-2) vs 3 (0-4), p=0.038). By day 5 the Uu+ve group had more emphysema and this
increased further by day 10
(score 1 (0-3) vs 0 (0-1) p=0.009).

Conclusion: Ventilated preterm infants infected with Uu have a specific clinical
and radiological course in the first 10 days. Their initial respiratory disease
is less severe but they then deteriorate with increasing ventilatory
requirements and more emphysematous change on X-ray. They have significantly
higher white cell counts suggesting ongoing inflammation.